People can't hear me on FaceTime for Mac

For several weeks, the FaceTime on my MacBook hasn't been working. On calls, we can see each other and I can hear them, but they can't hear me. I've confirmed the settings for the microphone are good and have rebooted the computer, which is running macOS 15.5 (24F74). People can hear me on Zoom, Google Meet with the microphone I hope to use with FaceTime app. What can I check to get this working?